The present invention is a toaster.
Most households are equipped with such an appliance. In the toasters known at present, one or more resistors, connected to a source of electrical current, usually the local supply circuit, face a chamber into which bread to be toasted is inserted. After a determined period of time, the heat cuts off and the toasted bread is taken out or is ejected from the appliance. In the most sophisticated apparatus, practice is to enclose the resistor(s) in quartz tubes to avoid the user=s coming in contact with an exposed conductor.
For safety reasons, the resistors are placed in an insulated casing which prevents users from burning themselves on contact with the appliance.
Unfortunately, these casings are opaque, which makes it difficult to see the state of the bread inside the appliance. For this reason, most toasters are equipped with a more or less sophisticated timer that automatically cuts off the electrical supply at the end of a determined time, which can be regulated.
The bread is toasted after a relatively slow rise in temperature, in a few seconds, after which it burns. Also, the toasting time varies with the physical qualities of the bread, such as the degree to which it is baked.
Thus, the purpose of the present invention is to solve the problems mentioned and to allow for visual monitoring of the toasting process, stopping it when the desired degree of toasting is reached.
The subject is thus a toaster, comprising a casing that is essentially parallelepiped in shape and heat insulated, and at least one electrical resistor which constitutes a radiant heating element enclosed in the casing, characterized in that the side walls of the casing are transparent.
It is thus possible to control the toasting and to stop it at the desired moment, depending on the user""s preference.
According to another characteristic of the invention, on each side of the casing, two heating elements are located at the top and bottom of the casing, respectively above and below the transparent plates that form the side walls of the casing, the heating elements being enclosed in reflective housings.
When the resistor is connected to the electrical supply, the bread is subjected to uniform radiation, mainly infrared, the major part of the emission spectrum being in this wavelength band.
According to another characteristic of the invention, the resistors are surrounded by reflectors of a curved sector of approximately 270E and the lower reflectors are mounted at a moveable angle with regard to the resistors, with means to control their movement between an off position, when they are turned downwards to form a protective guard, and an in-operation position, when they are turned towards a chamber holding the bread to be toasted.
These means of control consist of a cam mechanism comprising two small rods each mounted so that they can oscillate on the casing and each having one end with a hole in which there is a pin connected with a corresponding reflector, and a second end that moves jointly with a bread carrier.
This avoids having crumbs affecting the effectiveness of the reflectors and resistors when bread is inserted or taken out of the casing.
According to another characteristic of the invention, the side walls are made of double transparent, insulated glazing. They can also be made of non-shattering glass.
The inner surface of the glass plate(s) is preferably coated with a layer of metallic oxide that reflects the infrared rays. This layer may be colored so that the bread, irradiated by the infrared (which does not present optical problems) and partly by the red of the resistor, presents the color of ambient light. This problem can also be dealt with by including a filter on the transparent walls.